Book Image

Building RESTful Web Services with Spring 5 - Second Edition

By : Raja CSP Raman, Ludovic Dewailly
Book Image

Building RESTful Web Services with Spring 5 - Second Edition

By: Raja CSP Raman, Ludovic Dewailly

Overview of this book

REST is an architectural style that tackles the challenges of building scalable web services. In today's connected world, APIs have taken a central role on the web. APIs provide the fabric through which systems interact, and REST has become synonymous with APIs.The depth, breadth, and ease of use of Spring makes it one of the most attractive frameworks in the Java ecosystem. Marrying the two technologies is therefore a very natural choice.This book takes you through the design of RESTful web services and leverages the Spring Framework to implement these services. Starting from the basics of the philosophy behind REST, you'll go through the steps of designing and implementing an enterprise-grade RESTful web service. Taking a practical approach, each chapter provides code samples that you can apply to your own circumstances.This second edition brings forth the power of the latest Spring 5.0 release, working with MVC built-in as well as the front end framework. It then goes beyond the use of Spring to explores approaches to tackle resilience, security, and scalability concerns. Improve performance of your applications with the new HTTP 2.0 standards. You'll learn techniques to deal with security in Spring and discover how to implement unit and integration test strategies.Finally, the book ends by walking you through building a Java client for your RESTful web service, along with some scaling techniques using the new Spring Reactive libraries.
Table of Contents (21 chapters)
Title Page
Copyright and Credits
Packt Upsell
Spring Security and JWT (JSON Web Token)

Aspect-oriented programming (AOP)

Aspect-oriented programming is a concept where we add a new behavior to existing code without modifying the code itself. The AOP concept is really helpful when it comes to logging or method authentication.

There are many ways you can use AOP in Spring. Let's not get into much detail, as it will be a big topic to discuss. Here, we will discuss only the @Before pointcut and how to use @Before in our business logic.

AOP (@Before) with execution

The term execution in AOP means having a pointcut in the @Aspect annotation itself, and it doesn't depend on the controller API. The alternate way is that you will have to explicitly mention the annotation in the API call. Let's talk about the explicit pointcut in the next topic:

package com.packtpub.aop;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;
public class TokenRequiredAspect {  
  @Before("execution(* com.packtpub...